It is widely known that the earlier you detect cancer the better chance you have to survive it. However, what makes some cancer cases go undetected until it’s too late is that the symptoms can be vague sometimes. For most cancers, unexplained weight loss is the first sign, and sometimes it can be a welcome event to that person that may lead to delay in the diagnosis.
Pancreatic cancer is often referred to as silent cancer because symptoms can be vague at the beginning. The link below has a good description of the signs and symptoms of pancreatic cancer.